The widespread introduction and adoption of renewable energy technologies remains high on virtually every national development policy agenda; renewable energy systems can assist national energy autonomy, decentralize resource management, promote environmental conservation, and serve as a means to reduce global warming. The track record of efforts to turn this noble ideology into successful technology transfer and dissemination, however, remains very mixed. It is a story of a few successes amid many failures. Here we document and examine the diffusion of small-scale photovoltaic (PV) systems in Kenya. At the same time that integrated energy plans and top-down models championing renewable energy futures are becoming increasingly common, a new power base, divorced from these grand schemes, has begun to emerge. Over the past decade, some 20 000 to 40 000 small PV systems, essentially all privately financed, have been installed in Kenya. Many valuable lessons for renewable energy research can be found here. The Kenyan case richly illustrates the dramatic role that actors on every scale, from grassroots to international, can have in accelerating - or when mismanaged, impeding - technology transfer and the elevation of renewable energy systems from niche applications to a prominent role in household empowerment, and decentralized and sustainable development initiatives.